Muffle for sintering machines



Patented Nov. 27, 1928.

PATENT OFFICE.

JOSEPH CHARLES DEVICK, OF HELENA, MONTANA, ASSIGNOR TO AMERICAN SMELT-ING AND BEFINING COMPANY, OF NEW YORK, N. 55., A. CORPORATION OF JERSEY.

MUFFLE FOR SINTERINGMACHINES.

Application filed August 21, 1925. Serial No. 51,562.

My invention relates to an ignition device for firing the charge of oreon a moving grate, such as is found in a sintering machine.

It is usual in such constructions to position an open bottom mufileorhood above the top of the moving charge to be fired and eject liquidfuel into the muflie in such a manner that the down draft of air throughthe charge on such machines willdraw the flamesfrom the burning fuel inthe muffle down into the charge to ignite the same.

Such muifles have been formed with a metallic frame hung above themoving grate or conveyor and lined with fire resisting material. Carehas been taken in the past to pre vent the fire or too great heat fromreaching the metal frame, but the metal frame has warped and burnedthrough at times due to] the fire resisting material being broken awayand toot-her causes in spite of such care.

According to this invention a muflie is made up for the most part offire resisting material. The only metal associated with the burner is asingle. beam from which the various sections making up the mufiie arehung, and a single external clamping device for clamping the sectionstogether. If a section of the mufll-e burns out, as will occasionallyhappen in practice, it can be replaced with a minimum amount of labor.Furthermore, the invention makes provision allowing parts of the muffleto expand or-contract with changes in temperature without detrimentalresults to the fragile refractory fire resistingmaterial. .The metalparts are so positioned that they are subjected to a minimum amount ofheat and the possibility of fire directly touching them is remote.

Various other objects and advantages of the invention will be obviousfrom the following particular description of oneform of mechanismembodying my invention or from an inspection of the accompanyingdrawings; and the invention also consists'in certain new and novelfeatures of construction and combinations of parts hereinafter set forthand-claimed.

In the accompanying drawings I have shown for purposes of illustrationone form of mechanism embodying the invention, in which Fig. 1 is avertical longitudinal section of a muffle showing in broken lines the,moving conveyor or grate;

Fig. 2 is a front elevation thereof showing the opening to the burnerchamber;

F ig. 3 is a rear elevation; I I

Figtt is a section on the line l4-of Fig.1 through the combustionchamber; and

Fig. 5 is a fragmentary top plan view of one end of the muffie showingthe outline of the burner chamber.

In the following description and in the claims parts will be identifiedby specific namesfor convenience, but they are intended to be as genericin their application to similar parts as the art will permit. a

Referring now to the drawing, the muflie illustratedcomprises abu'rnersection 1, an end closuresection 3 and a plurality of like intermediatesections 2 therebetween.

The burner section 1 is preferably made of a refractory material such asfire clay'with a flat base wall 4 and arched wall 5 surgether making upan open bottom combustion chamber 9 Whose walls are coextensive with theinner opening of the burner chamber. The lower ends of the intermediatesections are disposed above the charge on the movable conveyor 7 butpreferably close thereto.

, An end closure section-3 is provided to close the end of the openbottom combustion chamber 9, and extends below the upper surface of theconveyor 7 alongside thereof in a manner similar to the burner section1;

Each of the intermediate sections 2 is provided with a tongue 12 on oneside and a groove 13 on the other extending throughout the extent of thearch wall thereof and coacting with similar cooperating grooves andtongues respectively on adjacent sections. The burner section 1 has agroove 14 and the end closure section 3 has tongue 15. 7

The upper end of each section is provided with an integral reducedattaching head 17 having an inverted T-shaped slot 18 in its top. Thelower end of each section is necessarily enlarged to accommodate thecomparatively large width of the combustion chamber while at the upperend of the section the size is smaller, the outer surface of eachsection converging upwardly.

The provision of these T-shaped slots 18 allows the sections tobesuspended by a support 19 above the conveyor which is well heatinsulatedfrom the great heat inside the combustion chamber by the material of thesections. The T-shap-ed slots allow easy assembly of the sections on thesupport 19 and easy removal in case a section should become defective.

To mount the muffle in position the various sections are threaded inorder on an I beam or other support 19 situated above the travelingconveyor 7, the end sections in the assembled muffle being positioned onopposite sides of the conveyor with the intermediate sectionstherebetween over the conveyor. To clamp the sections together and tohold them in assembled relation and also to prevent the tongue andgroove joints between the sections from leaking, a clamping device 20 isprovided. The clamping device comprises end clamping plates 21 locatedbetween the reduced attaching heads and the enlarged lower ends of thesections, and rods 22 embracing the attaching heads and resting againstthe enlarged lower ends connecting the plates. The rods may be threadedto take nuts which may bear against the outer surfaces of the end plates21.

It is, of course, obvious that sufficient material must be provided inthe attaching heads 17 to obviate the possibility of the sectionsbreaking due to their own weight. Also, it is obvious that the T-shapedslots should be made larger than the T-shaped end of the I-beam or othersupport 19, so that expansion of the support will not split thesections. Furthermore, the provision of the clamping device outside ofthe sections results in freedom from breakage because if the clampingdevice expands, the sections merely will become clamped less tightly.

in operation a burner (not shown) will be provided in the burner chamber6 and will eject suitable fuel into the combustion chamber 9. The burnerchamber and combustion chamber together form an ignition chamber wherethe incoming fuel will be burned with suflicient air to produce intenseheat which almost immediately ignites the charge on the conveyor.

It will easily be seen that the improved device can be made cheaply andis rugged, simple and eflicient in operation. The sections will be madeof fire resisting material such as fire clay, and due to the design ofthe muffle the parts may be made very large tails of the deviceillustrated and in its operation may be made by those skilled in the artwithout departing from the spirit of my I invention.

1 claim: r p p 1.. A muffle comprisinga plurality of one piece archshaped sections of fire resisting material having a fuel ignitionchamber, intel-fitting means between adjoining sections around saidchamber, and a clampingdevice for clampingsaid sections togetherincluding an elongated member extending between end sections. V

2. A muflie comprising a plurality of sections of fire resistingmaterial having a fuel ignition chamber, said sections having en largedlower portions and reduced upper attaching heads, and an externalclamping device surrounding said attaching heads for clamping saidsections together,

3. A muffle comprising a plurality of one piece arch shape sections offire resisting material having a burner chamber and an open bottomcombustion chamber, said sections having enlarged lower portionsanolreduced upper attaching heads, said sections having tongue and grooveconnections surrounding said chamber, and an external clamping devicesurrounding said attaching heads for clamping'said sections together.

4. A muflle comprising an end burner section having a burner chambertherein, an

intermediate section having an open bottom' compartment forming an openbottom combustion chamber coextensive with said burner chamber, an endclosure section for closing the end of said combustion chamber, saidsections being made of fire resisting material and being provided withintegral attaching heads at the tops thereof, said attaching heads beingprovided wit-h coextensive openings for suspension from a support, and aclamping device for clamping said sections together. a I V 5. A mufflecomprising an end burner section having a burner chamber therein, an

intermediate section having an open bottom compartment forming an openbottom combustion chamber coextensive with said burner chamber, an endclosure section for closing the end of said combustion chamber, saidsections having attaching heads at their upper ends provided With meansfor suspension from a support, and an external clamping device forclamping said sections together.

6. A muffle comprising a plurality of sections of fire resistingmaterial having a fuel ignition chamber, said sections having attachingmeans at their upper ends for suspension from a support, and a clampingdevice for clamping said sections together.

- In testimony whereof I have hereunto set my hand.

JOSEPH CHARLES DEVICK.

